Windows Store offers Drawboard PDF for Windows for $4.99. (You must buy it through the Windows Store App on a Windows 8.1 computer or device.) That's $5 off and the lowest price we could find for this app. It allows you to read, annotate, and markup PDFs via a touchscreen, stylus, or keyboard and mouse. Deal ends April 5.
Note that a free 3-day trial is also available.